Surgical devices and methods

ABSTRACT

An intravascular cutting device described herein uses high-pressure water, saline, or other fluid to cut tissue and other materials including but not limited to calcified tissue, stents, stent grafts, and other devices. In some embodiments, the cutting device includes a working end that has a nozzle with a hole to allow the release of a high-pressure fluid jet. Opposite of the nozzle is a catch plate or deflector anvil that prevents the fluid jet from cutting healthy tissue. The device user will place the item to be cut between the nozzle and catch plate and then advance the device along the item to be cut as the fluid jet is activated, thus cutting the object as it advances.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Stage application under 35 U.S.C. § 371of International Application No. PCT/US2018/037334, having anInternational Filing Date of Jun. 13, 2018, which claims the benefit ofU.S. Provisional Ser. No. 62/518,656 filed Jun. 13, 2017. The disclosureof the prior application is considered part of (and is incorporated byreference in) the disclosure of this application.

BACKGROUND 1. Technical Field

This document relates to devices and methods for intravascularmodifications. For example, this document relates to intravascularcutting devices that use high-pressure water, saline, or other fluid tocut tissue and other materials including but not limited to calcifiedtissue, stents, stent grafts, and other devices.

2. Background Information

Arterial dissection is a deadly disease caused by a tear in the tunicaintima of an artery, forming a false lumen. A thin wall or septumresulting from the tear creates a double barrel portion of the artery,with blood flow on both sides of the septum. The false lumen is on oneside of the septum while the true lumen is on the other side. Somearterial dissections can extend up to a meter in length. If untreated,death from rupture or downstream organ ischemia can occur. For patientsthat survive the initial episode, a chronic dissection occurs and oftenprogresses to an aneurysm with significant aortic rupture risk.

The main surgical method for arterial dissection reconstruction involvesopen surgical exposure of the artery and associated branch vessels,clamping of the arteries, and then cutting through all three layers ofthe artery in order to access and repair the dissection. Often thesurgeon adds a prosthetic graft to repair the artery wall andre-establish arterial continuity. Clamping arteries and cutting throughhealthy tissues to repair aortic dissections causes undesiredconsequences of extra stress placed on the heart with clamping,downstream organ dysfunction from lack of blood flow during clamping,and healthy tissue injury, such as nerve and lung injuries from surgicalexposures. Sometimes septum fenestration, or creating a cut in theseptum to connect the true and false lumens, is performed to relievedownstream organ ischemia.

A stent is a mesh, tube-like structure often used in conjunction withangioplasty to permanently hold open an artery, allowing forunrestricted blood flow, or to support a weakness in the artery wallcalled an aneurysm. In some cases, the artery reacts to the stent (e.g.,perceives it as a foreign body) and responds by mounting an immunesystem response which leads to further narrowing near or inside thestent. Restenosis is the recurrence of stenosis, a narrowing of a bloodvessel, leading to restricted blood flow. Restenosis usually pertains toan artery or other large blood vessel that has become narrowed, receivedtreatment to clear the blockage and subsequently become re-narrowed.Rates of restenosis differ between devices (e.g., stent-grafts, balloonangioplasty, etc.) and location of procedure (i.e., centrally located inthe heart, such as the coronary artery, or in peripheral vessels such asthe popliteal artery in the leg, the pudendal artery in the pelvis, orthe carotid artery in the neck). A 2003 study of selective andsystematic stenting for limb-threatening ischemia reported restenosisrates at one-year follow-up in 32.3% of selective stenting patients and34.7% of systematic stenting patients.

SUMMARY

This document describes devices and methods for intravascularmodifications. For example, this document describes intravascularcutting devices that use high-pressure water, saline, or other fluids tocut tissue and other materials including but not limited to calcifiedtissue, stents, stent grafts, valves, occluders, screws, implants, andother devices. In some embodiments, the cutting device includes aworking end that has a nozzle with a hole to allow the release of ahigh-pressure fluid jet. Opposite of the nozzle is a catch plate ordeflector anvil that prevents the fluid jet from cutting healthy tissue.The device user will place the item to be cut between the nozzle andcatch plate and then advance the device along the item to be cut as thefluid jet is activated, thus cutting the material as it advances.

In one aspect, this disclosure is directed to an intravascular cuttingdevice that includes a handle, a catheter extending distally from thehandle, and a cutting head extending distally from a distal end of thecatheter. In some embodiments, the catheter defines a first guidewirelumen and a second guidewire lumen. The first and second guidewirelumens extend along the catheter and distally terminate at respectivelocations through outer diameter wall surface of the catheter. Therespective locations can be proximal of a distal end of the catheter.The catheter can include a hypotube defining a cutting fluid conveyancelumen. The cutting head, extending distally from the distal end of thecatheter, defines a first cutting head guidewire lumen and a secondcutting head guidewire lumen. The cutting head can include a fluid jetprong defining a cutting head lumen in fluid communication with thecutting fluid conveyance lumen. The cutting head lumen distallyterminates at a nozzle opening. The cutting head can also include adeflector prong defining a cutting fluid deflection surface facingtoward the nozzle opening such that cutting fluid emitted from thenozzle opening strikes the cutting fluid deflection surface.

Such an intravascular cutting device can optionally include one or moreof the following features. The cutting head can be selectivelyattachable and detachable from the catheter by a user of theintravascular cutting device. The cutting head can be a first cuttinghead, and the intravascular cutting device can also include a secondcutting head that selectively attachable and detachable from thecatheter by a user of the intravascular cutting device. In someembodiments, the first cutting head guidewire lumen is radially alignedwith the fluid jet prong and/or the second cutting head guidewire lumenis radially aligned with the deflector prong. In some embodiments, thefirst cutting head guidewire lumen is not radially aligned with thefluid jet prong and/or the second cutting head guidewire lumen is notradially aligned with the deflector prong. In particular embodiments,the first cutting head guidewire lumen is radially outward of the fluidjet prong and/or the second cutting head guidewire lumen is radiallyoutward of the deflector prong. In some example embodiments, the firstcutting head guidewire lumen is radially inward of the fluid jet prongand the second cutting head guidewire lumen is radially inward of thedeflector prong. The fluid jet prong may comprise the hypotube of thecatheter such that the cutting head lumen is defined by the hypotube. Insome embodiments, the hypotube of the catheter distally terminatesproximal of the fluid jet prong. In particular embodiments of theintravascular cutting device, the cutting head defines an aspirationlumen that distally terminates between the fluid jet prong and thedeflector prong. The fluid jet prong may be pivotable in relation to thedeflector prong and/or the deflector prong may be pivotable in relationto the fluid jet prong, such that a separation distance betweenrespective distal ends of the fluid jet prong and the deflector prong isvariable. In some embodiments, the hypotube of the catheter is a firsthypotube and the cutting fluid conveyance lumen of the cutting head is afirst cutting fluid conveyance lumen. In some such embodiments, thecatheter also includes a second hypotube defining a second cutting fluidconveyance lumen, and both of the first and second cutting fluidconveyance lumens are in fluid communication with the cutting headlumen. Using such an arrangement, two cutting mediums can be mixed. Forexample, a suspended particulate matter can be mixed with a liquid toenhance the cutting performance of the fluid jet. In some embodiments,the intravascular cutting device also includes a valve arranged forselectively adjusting a mix ratio of fluids in the first and secondcutting fluid conveyance lumens.

In another aspect, this disclosure is directed to a method of cutting amaterial within a circulatory system of a patient. The method caninclude one or all of the following steps: deploying a first guidewirewithin the circulatory system; deploying a second guidewire within thecirculatory system and along an opposite side of the material inrelation to the first guidewire; advancing any embodiment of theintravascular cutting devices described herein over the first and secondguidewires such that the first guidewire is slidably disposed within:(i) the first guidewire lumen and (ii) the first cutting head guidewirelumen, and such that the second guidewire is slidably disposed within:(i) the second guidewire lumen and (ii) the second cutting headguidewire lumen; and supplying a cutting fluid into the cutting fluidconveyance lumen while the fluid jet prong and the deflector prong areon opposite sides of the material such that the cutting fluid: (i)sprays out of the nozzle opening, (ii) cuts through the material, and(iii) strikes the cutting fluid deflection surface.

Such a method of cutting a material within a circulatory system of apatient may optionally include one or more of the following features.During the advancing, the first and second guidewires may each extendalong an exterior of the catheter between: (i) the respective locationsthrough the outer diameter wall surface of the catheter and (ii) thefirst and second cutting head guidewire lumens. The material being cutmay be a soft tissue, a fabric of an implantable prosthetic device, ametal framework of an implantable prosthetic device, and/or any othertype of material without limitation. The method of cutting a materialwithin a circulatory system of a patient may also include aspirating thecutting fluid and particles of the material from between the fluid jetprong and the deflector prong while supplying the cutting fluid.

In another aspect, this disclosure is directed to a method of cutting astent located within a vessel of a patient. The method can include oneor all of the following steps: deploying a first guidewire through alumen of the stent; deploying a second guidewire exteriorly along thestent either within a wall of the vessel or outside of the vessel;deploying a stent graft within the lumen of the stent; advancing anyembodiment of the intravascular cutting devices described herein overthe first and second guidewires such that the first guidewire isslidably disposed within: (i) the first guidewire lumen and (ii) thefirst cutting head guidewire lumen, and such that the second guidewireis slidably disposed within: (i) the second guidewire lumen and (ii) thesecond cutting head guidewire lumen; and supplying a cutting fluid intothe cutting fluid conveyance lumen while the fluid jet prong and thedeflector prong are on opposite sides of the stent such that the cuttingfluid: (i) sprays out of the nozzle opening, (ii) cuts through thestent, and (iii) strikes the cutting fluid deflection surface.

Such a method of cutting a stent located within a vessel of a patientmay optionally include one or more of the following features. Thecutting fluid may include particulate matter. The method may alsoinclude aspirating the cutting fluid and particles of the stent frombetween the fluid jet prong and the deflector prong while supplying thecutting fluid.

Particular embodiments of the subject matter described in this documentcan be implemented to realize one or more of the following advantages.In some embodiments, conditions such as, but not limited to, arterialdissections and others can be treated using the devices and methodsprovided herein. In some embodiments, the devices and methods describedherein can be advantageously used to cut tough materials within the bodyof a patient. Such materials can include, but are not limited to,calcified lesions, metallic stents, metallic and fabric stent grafts,plastics, materials of prosthetic valves and other implantableprosthetic devices, bone screws, and other materials. In someembodiments, aspiration is used to mitigate creation of emboli. In someembodiments, various conditions can be treated in a minimally invasivefashion using the devices and methods provided herein. In comparison tomore invasive surgical approaches, such minimally invasive techniquescan reduce recovery times, patient discomfort, and treatment costs.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention pertains. Although methods and materialssimilar or equivalent to those described herein can be used to practicethe invention, suitable methods and materials are described herein. Allpublications, patent applications, patents, and other referencesmentioned herein are incorporated by reference in their entirety. Incase of conflict, the present specification, including definitions, willcontrol. In addition, the materials, methods, and examples areillustrative only and not intended to be limiting.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description herein. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an example intravascular cutting devicein accordance with some embodiments provided herein.

FIG. 2 is a perspective view of an example distal tip portion of theintravascular cutting device of FIG. 1.

FIG. 3 is perspective view of an example cutting head that can beincluded in some embodiments of the intravascular cutting devicesdescribed herein.

FIG. 4 is a longitudinal cross-sectional view of the cutting head ofFIG. 3.

FIG. 5 is perspective view of another example cutting head that can beincluded in some embodiments of the intravascular cutting devicesdescribed herein.

FIG. 6 is a longitudinal cross-sectional view of the cutting head ofFIG. 5.

FIG. 7 is side view of another example cutting head that can be includedin some embodiments of the intravascular cutting devices describedherein.

FIG. 8 is side view of another example cutting head that can be includedin some embodiments of the intravascular cutting devices describedherein.

FIG. 9 shows an example handle portion of the intravascular cuttingdevice of FIG. 1.

FIG. 10 is a flowchart of an example method for cutting a stent locatedwithin a vessel of a patient.

FIG. 11 is a perspective longitudinal cross-sectional view of anotherexample cutting head that can be included in some embodiments of theintravascular cutting devices described herein.

FIG. 12 is a side view of another example cutting head that can beincluded in some embodiments of the intravascular cutting devicesdescribed herein.

FIGS. 13-16 depict a sequence of steps of the example method of FIG. 10for cutting a stent located within a vessel of a patient.

FIG. 17 is perspective view of another example cutting head that can beincluded in some embodiments of the intravascular cutting devicesdescribed herein.

Like reference numbers represent corresponding parts throughout.

DETAILED DESCRIPTION

This document describes devices and methods for intravascularmodifications. For example, this document describes intravascularcutting devices that use high-pressure water, saline, or other fluids tocut tissue and other materials including but not limited to calcifiedtissue, stents, stent grafts, valves, occluders, screws, implants, andother devices. In some embodiments, the cutting device includes aworking end that has a nozzle with a hole to allow the release of ahigh-pressure fluid jet. Opposite of the nozzle is a catch plate ordeflector anvil that prevents the fluid jet from cutting healthy tissue.The device user will place the item to be cut between the nozzle andcatch plate and then advance the device along the item to be cut as thefluid jet is activated, thus cutting the material as it advances.

Within the nozzle is a fluid tube (which may be a hypotube) that conveysfluid from a pump. The fluid tube may be made of a variety of materialsincluding plastic, metal, plastic reinforced with metal braiding, etc.The fluid tube can be a variety of diameters. In general, the internaldiameter of the fluid tube is between 0.001″ and 0.100″ (0.0254 mm and2.54 mm). In another embodiment, the internal diameter of the fluid tubeis between 0.02″ and 0.05″ (0.508 mm and 1.27 mm). In one embodiment,the internal diameter of the fluid tube is about 0.024″ (0.6096 mm). Theinternal fluid tube may also taper at various point with in the device.So, in some areas the fluid tube may have a wider internal diameter andat other points it may have a narrower internal diameter. The fluid tubemay be in a straight line from the pump to the tip of the nozzle.Alternatively, the fluid tube may have bends or curves in it between thepump and the tip of the nozzle.

The nozzle contains a small hole that will allow the fluid jet to exitthe device and cut tissue or other materials. The fluid jet nozzle holediameter may range from 0.001″ to 0.020″ (0.0254 mm and 0.508 mm). Inone embodiment the fluid jet nozzle hole diameter is between 0.002″ and0.006″ (0.0508 mm and 0.1524 mm). In another embodiment the fluid jetnozzle hole diameter is between 0.003″ and 0.005″ (0.0762 mm and 0.127mm). The fluid jet hole may be positioned within the nozzle so that thefluid jet is emitted straight out of the nozzle and towards the catchplate. Alternatively the fluid jet nozzle hole may be positioned withinthe nozzle so that the fluid jet is emitted at an angle towards thecatch plate (e.g., the fluid jet is emitted at a slight downward angleinto the catch plate). In some embodiments, the angle may be between 1°and 40°. In another embodiment, the angle may be between 10° and 30°.The nozzle may also contain a notch around the fluid jet nozzle hole.The nozzle may sit next to a back plate. This back plate can be used toconnect guidewires to the device.

The catch plate can be made of a variety of materials including but notlimited to metals and plastics. The catch plate can be curved orstraight. The catch plate can have a variety of widths. In oneembodiment, the catch plate takes up between 10% to 80% of thecircumference of the tip of the device. In another embodiment, the catchplate takes up between 20% to 60% of the circumference of the tip of thedevice. In another embodiment, the catch plate takes up between 20% to50% of the circumference of the tip of the device. In one embodiment,the catch plate sits around the catheter portion of the device.

The device may be packaged within a catheter. The catheter can be madefrom a variety of materials including but not limited to plastics suchas thermoplastic elastomers (e.g., Pebax®). The catheter may havemultiple lumens. The fluid tube will be contained within the catheter.Other components such as suction and imaging devices can be packagedwithin the catheter. The catheter may also contain guidewires.

The device may use guidewires. The guidewires may be contained fullywithin the catheter or the guidewires may sit outside of the catheter,or the guidewires may sit outside of one section of the catheter and becontained within the catheter in another section. In one embodiment theguidewires exit the catheter, run along the outside of the catheter, andare attached to the back side (outside) of the catch plate and the backside (outside) of the back plate that is next to the nozzle.

The device of the present invention can be used to treatdiseases/disorders. In one embodiment the device is used to cut tissuesepta. In one embodiment the tissue septum is due to an arterial orvenous dissection. In one embodiment the dissection includes but is notlimited to an aortic dissection, a carotid artery dissection, avertebral artery dissection, and coronary artery dissection. The deviceof the present invention may also be used to cut non-biologicalmaterials including but not limited to stents, stent grafts, cathetersetc.

Additional component descriptions and methods of use are described inU.S. patent application Ser. No. 14/548,046 filed on Nov. 19, 2014,incorporated by reference herein in its entirety.

Referring to FIG. 1, an example intravascular cutting device 100, inaccordance with some embodiments provided herein, can be used to cuttissue and other materials including but not limited to calcifiedtissue, bone, stents, stent grafts, and other materials and deviceswithin the body of a patient in a minimally invasive manner. Asdescribed further herein, the intravascular cutting device 100 can beconfigured in many different arrangements, can include one or morevarious optional features, and can be used in many different manners.All possible combinations and permutations of arrangements, features,and uses are within the scope of this disclosure. Moreover, thedescriptions provided herein are not to be construed as limiting, andone of ordinary skill in the art will readily envision and comprehendadditional analogous arrangements, features, and uses of theintravascular cutting device 100 beyond those expressly describedherein, which are also within the scope of this disclosure.

The example intravascular cutting device 100 broadly includes a handle110, a catheter 120, and a cutting head 140. The catheter 120 isattached to, and extends distally from, the handle 110. The cutting head140 is attached to, and extends distally from, a distal end portion ofthe catheter 120. In some embodiments, the cutting head 140 isselectively attachable and detachable from the catheter 120 such that aclinician user can select different types or sizes of cutting heads fordifferent purposes.

The handle 110 can be connected to various other supportivedevices/systems. For example, in some cases one or more pumps can beconnected to the handle 110. Such one or more pumps can serve as asupply of pressurized cutting fluids. In some cases, a source of vacuumcan be connected to the handle 110. Such a vacuum source can providesuction for aspiration at the cutting head 140. In some cases, thehandle 110 includes one or more actuators or control mechanisms. Forexample, the handle 110 can include a trigger, button, tab, lever, knobor other type of actuator that can be used by a clinician to startand/or stop a supply flow of cutting fluid to the cutting head 140. Insome embodiments, the handle 110 can include a trigger, button, tab,lever, knob, or other type of actuator that can be used by a clinicianto start and/or stop suction for aspiration at the cutting head 140. Inparticular embodiments, one or more portions of the catheter 120 can beselectively deflectable for steering purposes and the user-controls forthe deflection can be located at/on the handle 110. In some embodiments(e.g., as shown in FIG. 9), one or more guidewires 104 a and 104 benter/exit from ports of the handle 110, and slidably pass throughlumens defined within the handle 110.

The example intravascular cutting device 100 also includes the catheter120 that is attached to, and extends distally from, the handle 110. Thecatheter 120 terminates at a distal end portion, to which the cuttinghead 140 is attached. The catheter 120 can be laterallyflexible/compliant while being sufficiently kink resistant. In someembodiments, the catheter 120 can be used within a working channel of anendoscope or laparoscope. In some embodiments, the catheter 120 can beadapted to be used in conjunction with a tele-operated surgical system(“robotic” surgical system).

The catheter 120 can be made of any suitable material and combinationsof materials. For example, in some embodiments the catheter 120 can bemade from polymeric materials such as, but not limited to,polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP),HYTREL®, nylon, PICOFLEX®, PEBAX®, TECOFLEX®, and the like, andcombinations thereof. In alternative embodiments, the catheter 120 canbe made from metallic materials such as, but not limited to, nitinol,stainless steel, stainless steel alloys, titanium, titanium alloys, andthe like, and combinations thereof. In some embodiments, the catheter120 can be made from combinations of such polymeric and metallicmaterials (e.g., polymer layers with metal braid, coil reinforcement,stiffening members, and the like, and combinations thereof). Someportions of the catheter 120 can be constructed differently from otherportions of the catheter 120. For example, in some embodiments portionsof the catheter 120 near to the handle 110 can be constructed to havemore stiffness or column strength in comparison to portions of thecatheter 120 near to the cutting head 140 that can be constructed tohave more compliance or flexibility.

Referring also to FIG. 2, in some embodiments the catheter 120 can be anextrusion that defines multiple lumens therein. For example, in thedepicted embodiment, the catheter 120 defines at least two lumens thateach slidably receive a guidewire 104 a/104 b therein. In the depictedembodiment, the two guidewire lumens defined within the catheter 120distally terminate at respective locations 122 a and 122 b through outerdiameter wall surface of the catheter 120. The respective locations 122a and 122 b are located proximal of a distal end of the catheter 120. Inthe depicted embodiment, the first and second guidewires 104 a and 104 beach extend along an exterior of the catheter 120 between: (i) therespective locations 122 a and 122 b through the outer diameter wallsurface of the catheter 120 and (ii) the cutting head 140 (including thefirst and second cutting head guidewire lumens of the cutting head 140).In some embodiments, the catheter 120 defines one or more additionallumens for features such as aspiration, insufflation, visualization,cauterization, medicant supply, and the like.

Referring also to FIGS. 3 and 4, the catheter 120 includes and encases ahypotube 130 that defines a lumen for conveying a cutting fluid. In thedepicted embodiment, the hypotube extends through an entire length ofthe catheter 120 and extends from a distal end of the catheter 120 intothe cutting tip 140. The hypotube 130 can include one or more smoothbends along its length (e.g., see FIG. 4). While the depicted embodimentincludes a single hypotube 130 for conveying cutting fluid. In someembodiments, two or more hypotubes 130 are included that can merge twoor more different types of fluids/solutions that can include particulatein some cases.

The hypotube 130 can be constructed of any suitable material. Forexample, in some embodiments the hypotube 130 made of stainless steel,nitinol, titanium, other metallic materials, or a polymeric material,without limitation. The hypotube 130 can be scalable to any suitablesize in terms of wall thickness and lumen diameter. For example, in someembodiments the hypotube 130 is an 18TW gauge hypotube with an outerdiameter of 0.05 inches (1.27 mm), an inner diameter of 0.0380 inches(0.965 mm), and a wall thickness of 0.0060 inches (0.152 mm). In anotherexample embodiment, the hypotube 130 is a 20RW gauge hypotube with anouter diameter of 0.0355 inches (0.902 mm), an inner diameter of 0.0235inches (0.597 mm), and a wall thickness of 0.0060 inches (0.152 mm). Thehypotube 130 can be treated to obtain a suitable stiffness/complianceand kink resistance.

The cutting head 140 is attached to and extends distally from the distalend of the catheter 120. In some embodiments, the cutting head 140 isselectively attachable and detachable from the catheter 120 such that aclinician user can select different types or sizes of cutting heads fordifferent purposes. Alternatively, in some embodiments the cutting head140 can be permanently affixed to the distal end of the catheter 120.

In some embodiments, the cutting head 140 is made of a hypotube that isformed to define a fluid jet prong 150 and a deflector prong 160. Inparticular embodiments, the cutting head 140 is made is other mannerssuch as, but not limited to, 3D printing, over-printing, molding,over-molding, machining, laser cutting, and the like, and combinationsthereof. The fluid jet prong 150 and the deflector prong 160 can bepositioned on opposite sides of the cutting head's longitudinal axis102. For example, the fluid jet prong 150 and the deflector prong 160can be positioned (e.g., centered) at radial positions that are about180 degrees apart from each other about the longitudinal axis 102.

In the depicted embodiment, the hypotube 130 extends into the cuttingtip and becomes attached to, or a part of, the fluid jet prong 150.Accordingly, the hypotube 130 defines a cutting head lumen that conveysa cutting fluid from the catheter 120. In other words, the cutting headlumen of the fluid jet prong 150 is in fluid communication with thecutting fluid conveyance lumen of the hypotube 130 in the catheter 120.In some embodiments, the hypotube 130 is attached (e.g., by welding) tothe fluid jet prong 150.

The cutting head lumen defined by the hypotube 130 in the fluid jetprong 150 distally terminates at a nozzle opening 132. The nozzleopening 132 is the location from which a fine high-pressure jet ofcutting fluid is expelled out of the hypotube 130 such that it can cut amaterial positioned between the fluid jet prong 150 and the deflectorprong 160. In the depicted embodiment, the nozzle opening 132 is a holedefined through the wall of the hypotube 130.

The deflector prong 160 blocks the high-pressure jet of cutting fluidthat is expelled from the nozzle opening 132 from contacting othertissue or materials that are not intended to be cut. Hence, thedeflector prong 160 acts as a backstop or anvil in relation to the jetof cutting fluid. The deflector prong 160 can be specifically designedto disperse the fluid energy of the cutting fluid expelled from thenozzle opening 132. In some embodiments, the deflector prong 160 isshaped like a concave trough that extends parallel to the cutting headaxis 102.

Still referring to FIGS. 1-4, the cutting head 140 defines a firstcutting head guidewire lumen 142 a and a second cutting head guidewirelumen 142 b within which the guidewires 104 a and 104 b, respectively,are slidably received. Thus, the guidewires 104 a-b extend through thetwo guidewire lumens defined within the catheter 120, exit respectivelocations 122 a and 122 b through outer diameter wall surface of thecatheter 120, extend along an exterior of the catheter 120, and thenextend through the first and second cutting head guidewire lumens 142a-b. The guidewires 104 a-b are placed in the patient first, and theintravascular cutting device 100 is then advanced over the guidewires104 a-b. Accordingly, the guidewires 104 a-b are used to position thecutting head 140 in the desired location and orientation for cutting oneor more materials as desired by a clinician user. In other words, theguidewires 104 a-b can be installed on opposite sides of the material(s)to be cut, and then by virtue of the advancement of the intravascularcutting device 100 over the guidewires 104 a-b the material(s) to be cutwill be positioned between the fluid jet prong 150 and the deflectorprong 160. The material to be cut can include, but is not limited to,soft tissue, calcified tissue, bone, fabrics, metal frames, plastics,stents, stent grafts, valves, occluders, screws, implants, and othernative materials and/or implanted prosthetic materials.

In the depicted embodiment, the first cutting head guidewire lumen 142 ais radially aligned with the fluid jet prong 150, and the second cuttinghead guidewire lumen 142 b is radially aligned with the deflector prong160. Moreover, in the depicted embodiment the first cutting headguidewire lumen 142 a is radially outward of the fluid jet prong 150,and the second cutting head guidewire lumen 142 b is radially outward ofthe deflector prong 160. In some embodiments, the first cutting headguidewire lumen 142 a is not radially aligned with the fluid jet prong150, and/or the second cutting head guidewire lumen 142 b is notradially aligned with the deflector prong 160. Moreover, in someembodiments the first cutting head guidewire lumen 142 a is radiallyinward of the fluid jet prong 150, and/or the second cutting headguidewire lumen 142 b is radially inward of the deflector prong 160.

Referring to FIGS. 5 and 6, another example embodiment of a cutting head140′ can be used as part of the intravascular cutting device 100. Inthis example, the cutting head 140′ includes features that are analogousto the cutting head 140 described above, and such analogous features areidentified by the same reference number including a prime symbol.However, the cutting head 140′ is different from the cutting head 140 inthat the hypotube 130′ is capped by a tip 134 that defines a nozzleopening 136 that directs the high-pressure jet of cutting fluid towardthe deflector prong 160′.

Referring to FIG. 7, another example embodiment of a cutting head 240can be used as part of the intravascular cutting device 100. The cuttinghead 240 includes a fluid jet prong 250 and a deflector prong 260. Thecutting head 240 defines a first cutting head guidewire lumen 242 a, asecond cutting head guidewire lumen 242 b, and a nozzle opening 232.

The cutting head 240 is configured to couple with a hypotube of thecatheter 120 (refer to FIGS. 1 and 2) that distally terminates proximalof the fluid jet prong 250. Accordingly, the cutting head 240 defines ahypotube receptacle 270 that receives a distal end portion of thehypotube of the catheter 120. When the distal end portion of thehypotube of the catheter 120 is positioned in the hypotube receptacle270, the cutting fluid conveyance lumen of the hypotube is in fluidcommunication with a cutting head fluid conveyance lumen 230 definedwithin the fluid jet prong 250. The cutting head fluid conveyance lumen230 distally terminates at the nozzle opening 232.

The cutting head 240 can be 3D printed in some embodiments. In some suchembodiments, the deflector prong 260 includes a metallic insert that thefluid jet will strike against. 3D printing readily allows forreconfiguration and customization of the design of the cutting head 240.For example, FIG. 8 shows a variation that includes a different designof cutting head fluid conveyance lumen 230′ and nozzle 232′.

Referring to FIG. 10, an example method 300 can be performed using theintravascular cutting devices described herein to cut a tough material,such as a stent, located within a vessel of a patient. FIG. 13illustrates such a stent 20 within a vessel 10. While this examplemethod 300 pertains to the cutting of a stent, in situ, it should beunderstood that the method 300 can also be readily adapted to cuttingother materials such as, but not limited to, stent grafts, prostheticvalves, occluders, bone screws, calcified lesions, bone, and the like.

Still referring to FIG. 10, in step 310, a first guidewire is deployedthrough a lumen of the stent to be cut. In step 320, a second guidewireis deployed exteriorly along the stent either within a wall of thevessel or outside of the vessel. In particular, the second guidewirewill be advanced through the lumen of the vessel, then either within thewall of the vessel or outside of the vessel along the location of thestent, and then back into the lumen of the vessel on the other side ofthe stent. This arrangement is illustrated in FIG. 14, which includesthe first guidewire 400 deployed through the lumen of the stent 20 andthe second guidewire 410 deployed exteriorly along the stent 20 eitherwithin the wall of the vessel 10 or outside of the vessel 10 (here thesecond guidewire 410 is depicted outside of the vessel 10).

Still referring to FIG. 10, in step 330, a stent graft is deployedwithin the lumen of the stent or exteriorly to the stent but within thevessel. The stent graft will extend both distally and proximally beyondthe length of the stent. This arrangement is illustrated in FIG. 15,which includes the stent graft 430. As depicted in FIG. 16, the stentgraft 430 will be expanded to seal against the inner wall of the vessel10 both proximally and distally of the stent 20.

Still referring to FIG. 10, in step 340, an intravascular cutting device(such as any embodiment of the intravascular cutting device 100described herein) is advanced over the first and second guidewires. Theintravascular cutting device can be configured in accordance with any ofthe embodiments and optional features described herein. By virtue of theplacements of the first and second guidewires on opposite sides of thestent, when the intravascular cutting device is advanced over theguidewires an edge portion of the stent will be positioned between thefluid jet prong and the deflector prong of the intravascular cuttingdevice.

In step 350, a cutting fluid is supplied into the cutting fluidconveyance lumen of the intravascular cutting device while the fluid jetprong and the deflector prong are on opposite sides of the stent.Accordingly, the cutting fluid will: (i) spray out of the nozzleopening, (ii) cut through the stent, and (iii) strike the cutting fluiddeflection surface. The intravascular cutting device can be advancedalong the stent while the cutting fluid is supplied. In that manner, theentire length of the stent can be cut.

During and after the cutting, the deployed stent graft serves as aprosthetic vessel lumen for the vessel (even if the wall of the vesselis cut in conjunction with the cutting of the stent). In someembodiments, the method 300 also includes aspiration of fluids and stentmaterial particles from between the fluid jet prong and the deflectorprong.

In some embodiments, in order to enhance the cutting performance of thecutting fluid, particulate can be added to the cutting fluid to increasethe abrasive properties of the cutting fluid. Such particulate can beespecially advantageous for cutting tough materials, such as the stent(made of metal) described in the method 300. In some embodiments, theparticulate can be sodium chloride crystals, for example. Thecrystals/particulate can be suspended in solution and can be of theproper size to be expelled through the nozzle opening of the cuttinghead.

In some such embodiments, crystals or other types of particulate can beadded directly to the source of cutting fluid that is then pumpedthrough the intravascular cutting device. In other embodiments, thecrystals or other types of particulate can be in a separate solutionthat is mixed with the primary source of cutting fluid at a point withinthe intravascular cutting device. In such a case, the catheter of theintravascular cutting device can include a first hypotube for conveyingthe primary cutting fluid and a second hypotube for conveying thesolution containing the crystals or other types of particulate. The twohypotubes can each be confluent with and in fluid communication with thecutting head lumen.

In some embodiments, the two hypotubes conjoin such that the fluids canmix in a ratio that is selectively adjustable. In some such embodiments,a valve such as an adjustable needle valve is used to adjustably-mix theprimary cutting fluid and the solution containing the crystals or othertypes of particulate.

Referring to FIG. 11, another example cutting head 140″ can be used aspart of the intravascular cutting device 100 (FIG. 1). In this example,the cutting head 140″ includes features that are analogous to thecutting head 140 described above (refer to FIG. 4). However, the cuttinghead 140″ is different from the cutting head 140 in that the nozzleopening 132″ that directs the high-pressure jet of cutting fluid towardthe deflector prong 160″ is positioned more proximally than the nozzleopening 132 of the cutting head 140. In the depicted embodiment, thenozzle opening 132″ directs the high-pressure jet of cutting fluidtoward the deflector prong 160″ at a location on the deflector prong160″ that is proximal of the middle of the deflector prong 160″.

Referring to FIG. 12, another example cutting head 240″ can be used aspart of the intravascular cutting device 100 (FIG. 1). In this example,the cutting head 240″ includes features that are analogous to thecutting head 240′ described above (refer to FIG. 8). However, thecutting head 240″ is different from the cutting head 240′ in that itincludes an aspiration port and lumen 280″ defined within the deflectorprong 260″. Alternatively or additionally, an aspiration port and lumencan be defined within the fluid jet prong 250″.

Additional Optional Features

In some embodiments, the cutting head and/or the catheter of theintravascular cutting devices described herein are configured tofacilitate aspiration of fluids and/or particles from between the fluidjet prong and the deflector prong. For example, as shown in FIG. 6, anaspiration port and lumen 180′ can be positioned between the fluid jetprong 150′ and the deflector prong 160′. In some such embodiments, theaspiration port and lumen 180′ is positioned at the base of thedeflector prong 160′. Other arrangements of aspiration ports and lumensare described in reference to FIG. 12.

Referring to FIG. 17, in some embodiments of the intravascular cuttingdevices described herein, the cutting head 240′″ includes a deflectorprong 260′″ that is pivotable (e.g., hinged) in relation to the fluidjet prong 250′″ such that a separation distance between respectivedistal ends of the fluid jet prong 250′″ and the deflector prong 260′″is variable. In some such cases, the deflector prong 260′″ isselectively pivotable in relation to the fluid jet prong 250′″ such thata separation distance between respective distal ends of the fluid jetprong 250′″ and the deflector prong 260′″ is controllably variable by aclinician user. In other words, in some embodiments the deflector prong260′″ can pivot radially toward and/or radially away from the centrallongitudinal axis 102 of the cutting head 240′″ (e.g., as also depictedby arrows 262 of FIGS. 7 and 17). In some such cases, the deflectorprong 260′″ is pivotable while also being spring biased toward anorientation in which it is parallel with the longitudinal axis 102 ofthe cutting head 240′″.

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of anyinvention or of what may be claimed, but rather as descriptions offeatures that may be specific to particular embodiments of particularinventions. Certain features that are described in this specification inthe context of separate embodiments can also be implemented incombination in a single embodiment. Conversely, various features thatare described in the context of a single embodiment can also beimplemented in multiple embodiments separately or in any suitablesubcombination. Moreover, although features may be described herein asacting in certain combinations and even initially claimed as such, oneor more features from a claimed combination can in some cases be excisedfrom the combination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. In certain circumstances, multitasking and parallel processingmay be advantageous. Moreover, the separation of various system modulesand components in the embodiments described herein should not beunderstood as requiring such separation in all embodiments, and itshould be understood that the described program components and systemscan generally be integrated together in a single product or packagedinto multiple products.

Particular embodiments of the subject matter have been described. Otherembodiments are within the scope of the following claims. For example,the actions recited in the claims can be performed in a different orderand still achieve desirable results. As one example, the processesdepicted in the accompanying figures do not necessarily require theparticular order shown, or sequential order, to achieve desirableresults. In certain implementations, multitasking and parallelprocessing may be advantageous.

What is claimed is:
 1. An intravascular cutting device, comprising: ahandle; a catheter extending distally from the handle and defining afirst guidewire lumen and a second guidewire lumen, the first and secondguidewire lumens extending along the catheter and distally terminatingat respective locations through an outer diameter wall surface of thecatheter, the respective locations being proximal of a distal end of thecatheter, the catheter comprising a hypotube defining a cutting fluidconveyance lumen; and a cutting head extending distally from the distalend of the catheter and defining a first cutting head guidewire lumenand a second cutting head guidewire lumen, the cutting head comprising:a fluid jet prong defining a cutting head lumen in fluid communicationwith the cutting fluid conveyance lumen, the cutting head lumen distallyterminating at a nozzle opening; and a deflector prong defining acutting fluid deflection surface facing toward the nozzle opening suchthat cutting fluid emitted from the nozzle opening strikes the cuttingfluid deflection surface.
 2. The intravascular cutting device of claim1, wherein the cutting head is selectively attachable and detachablefrom the catheter by a user of the intravascular cutting device.
 3. Theintravascular cutting device of claim 2, wherein the cutting head is afirst cutting head, and further comprising a second cutting head that isselectively attachable and detachable from the catheter by a user of theintravascular cutting device.
 4. The intravascular cutting device ofclaim 1, wherein the first cutting head guidewire lumen is radiallyaligned with the fluid jet prong and the second cutting head guidewirelumen is radially aligned with the deflector prong.
 5. The intravascularcutting device of claim 4, wherein the first cutting head guidewirelumen is radially outward of the fluid jet prong and the second cuttinghead guidewire lumen is radially outward of the deflector prong.
 6. Theintravascular cutting device of claim 1, wherein the fluid jet prongcomprises the hypotube such that the cutting head lumen is defined bythe hypotube.
 7. The intravascular cutting device of claim 1, whereinthe hypotube distally terminates proximal of the fluid jet prong.
 8. Theintravascular cutting device of claim 1, wherein the cutting headfurther defines an aspiration lumen that distally terminates between thefluid jet prong and the deflector prong.
 9. The intravascular cuttingdevice of claim 1, wherein the fluid jet prong is pivotable in relationto the deflector prong or the deflector prong is pivotable in relationto the fluid jet prong, such that a separation distance betweenrespective distal ends of the fluid jet prong and the deflector prong isvariable.
 10. The intravascular cutting device of claim 1, wherein thehypotube is a first hypotube and the cutting fluid conveyance lumen is afirst cutting fluid conveyance lumen, and wherein the catheter furthercomprises a second hypotube defining a second cutting fluid conveyancelumen, and wherein both of the first and second cutting fluid conveyancelumens are in fluid communication with the cutting head lumen.
 11. Theintravascular cutting device of claim 10, further comprising a valvearranged for selectively adjusting a mix ratio of fluids in the firstand second cutting fluid conveyance lumens.
 12. A method of cutting amaterial within a circulatory system of a patient, the methodcomprising: deploying a first guidewire within the circulatory system;deploying a second guidewire within the circulatory system and along anopposite side of the material in relation to the first guidewire;advancing the intravascular cutting device of claim 1 over the first andsecond guidewires such that the first guidewire is slidably disposedwithin: (i) the first guidewire lumen and (ii) the first cutting headguidewire lumen, and such that the second guidewire is slidably disposedwithin: (i) the second guidewire lumen and (ii) the second cutting headguidewire lumen; and supplying a cutting fluid into the cutting fluidconveyance lumen while the fluid jet prong and the deflector prong areon opposite sides of the material such that the cutting fluid: (i)sprays out of the nozzle opening, (ii) cuts through the material, and(iii) strikes the cutting fluid deflection surface.
 13. The method ofclaim 12, wherein, during the advancing, the first and second guidewireseach extend along an exterior of the catheter between: (i) therespective locations through the outer diameter wall surface of thecatheter and (ii) the first and second cutting head guidewire lumens.14. The method of claim 12, wherein the material is soft tissue.
 15. Themethod of claim 12, wherein the material is a fabric of an implantableprosthetic device.
 16. The method of claim 12, wherein the material ismetal framework of an implantable prosthetic device.
 17. The method ofclaim 12, further comprising aspirating the cutting fluid and particlesof the material from between the fluid jet prong and the deflector prongwhile supplying the cutting fluid.
 18. A method of cutting a stentlocated within a vessel of a patient, the method comprising: deploying afirst guidewire through a lumen of the stent; deploying a secondguidewire exteriorly along the stent either within a wall of the vesselor outside of the vessel; deploying a stent graft within the lumen ofthe stent; advancing the intravascular cutting device of claim 1 overthe first and second guidewires such that the first guidewire isslidably disposed within: (i) the first guidewire lumen and (ii) thefirst cutting head guidewire lumen, and such that the second guidewireis slidably disposed within: (i) the second guidewire lumen and (ii) thesecond cutting head guidewire lumen; and supplying a cutting fluid intothe cutting fluid conveyance lumen while the fluid jet prong and thedeflector prong are on opposite sides of the stent such that the cuttingfluid: (i) sprays out of the nozzle opening, (ii) cuts through thestent, and (iii) strikes the cutting fluid deflection surface.
 19. Themethod of claim 18, wherein the cutting fluid comprises particulatematter.
 20. The method of claim 18, further comprising aspirating thecutting fluid and particles of the stent from between the fluid jetprong and the deflector prong while supplying the cutting fluid.